Adding CLI commands to tune NIC performance.

1. Set by default CPU in performance mode.
2. Check if nic supports RSS and if it is not enabled by default, turn it on.
3. If NIC supports, set the RSS queue count equal to the number of cores
4. If NIC supports, enable ntuple by default.
5. Add CLI command to watch CPU frequency.
6. Add CLI command to configure and show Interrupt Coalescence (IC) - rx-usecs, tx-usecs, rx-frames, tx-frames (hardware IRQ)
7. Add CLI command to configure, show, and monitor Interrupt Coalescing (soft IRQ) net.core.netdev_budget_usecs, net.core.netdev_budget
8. Add CLI command to configure, show, and monitor Network device backlog queue net.core.netdev_max_backlog
9. Add CLI command to change RSS queue count.
10. Add CLI command to enable esp-hw-offload if a NIC supports it.